The present invention relates to a semiconductor device, and for example, is a technique that can be applied to a power device.
A transistor using a nitride semiconductor layer may be used for a power device. Japanese Patent Laid-Open No. 2014-22413 (Patent literature 1) describes an example of such a power transistor. In the transistor described in Patent literature 1, an interlayer insulating film is formed over the nitride semiconductor layer. In addition, a drain pad, a source pad, a drain electrode, and a source electrode are provided over the interlayer insulating film. The drain electrode is provided to the drain pad in a comb teeth shape. In the same way, the source electrode is provided to the source pad in a comb teeth shape. In this case, the drain electrode and the source electrode are arranged to engage with each other.
Furthermore, in Patent literature 1, the drain electrode includes a recessed portion formed in the interlayer insulating film inside the drain electrode, in a plan view. A part of the drain electrode is buried in the recessed portion. The drain electrode is electrically coupled to the nitride semiconductor layer via the recessed portion. In the same way, the source electrode includes a recessed portion formed in the interlayer insulating film inside the source electrode in a plan view. A part of the source electrode is buried in the recessed portion. The source electrode is electrically coupled to the nitride semiconductor layer via the recessed portion.